B-20 - Soviet small- caliber aviation automatic gun of 20 mm caliber. Created by the weapons designer M.E. Berezin during World War II by reworking his 12.7-mm machine gun UB with a 20 mm ShVAK gun cartridge [3] for the competition, which also involved the designs of the B-20 Vladimirov and the Sh-20 Shpitalnaya [ 4] (according to other sources, [5] the third participant was ShA-20 Shpitalnaya).
| B-20 | |
|---|---|
 | |
| Carriers | |
| IL-10 , La-7 , Tu-4 , Yak-3 , Yak-9 and others. See below for more details. | |
| Sizes, mm | |
| Length | 2035 |
| Width | 151 |
| Weight | |
| Shell weight, g | 96 [mon 1] [1] |
| Cartridge weight, g | 180 [1] |
| Gun weight, kg | 25 |
| Specifications | |
| Caliber mm | 20 |
| The number of trunks | one |
| Ammunition, cartridges | 170-240 [sn 2] [2] |
| Rate of fire | |
| Rate of fire, rds / min | 600-800 |
| Initial speed, m / s | 800 |
| Continuous queue length standing | ? |
 External Images | |
|---|---|
 | B-20 (second from left) , near ShVAK , VYA-23 and UB |
Content
Creation History
The development of the gun began in 1941 , on July 11 of that year, GKO Decree No. 106 “On Testing a 20 mm Berezin Air Gun” [6] was issued. It was planned to conduct factory tests of two guns before July 16, prepare three guns for field tests by 18 , and install two wing guns on the Il-2 and one engine gun on LaGG-3 by July 25 and conduct flight tests [7] .
In the memoirs of the deputy commissar of armaments of V. N. Novikov , it is stated that the gun only got to the first tests at the end of 1943 [8] . According to him, the main difficulties arose with the alteration of the shutter and receiver [9] . The problems were probably caused by the fact that the ShVAK gun cartridge, unlike the UB machine gun cartridge , had a rim . Thanks to close cooperation with factory designers, the gun turned out to be not only very light (twice as light as ShVAK), but also much more technologically advanced than the last [9] .
Design
Despite Shirokorad ’s claims that there are no design differences between the gun and the “parent” machine gun [3] , there is detailed information about such differences [4] . The main change was that the wedge locking of the bolt during firing was carried out with a vertical wedge located along the axis of the gun, and not with the side one, like with a machine gun [4] .
The shutter was divided into two parts - the cartridge extractor from the receiver, coupled to the slider , and the shutter itself, movably connected to the slider [4] .
In addition, the extraction of the cartridge from the receiver during the firing of the gun started without an initial speed, more smoothly - the extraction of the machine gun took place at the initial speed acquired by the slider during free play in the rear position, which could cause unprotecting (early separation of the bullet from the cartridge case) [4 ] .
Berezin also developed a new pneumatic reloading mechanism without an auxiliary cylinder, electrification was widely used for the first time (an electric trigger mechanism and electric gun readiness sensors were developed) [4] .
Production
The B-20 was adopted by GKO Decree No. 6681 “On the Adoption of the Red Army Air Force of the Lightweight B-20 Caliber 20 mm Aviation Automatic Cannon Designed by Comrade Berezin” on October 10, 1944 [10] . It is known that from March 1945 until the end of the war, 368 “three-gun” La-7s were produced, all at plant No. 381 [11] .
Already after putting into service, it turned out that the gun does not meet the requirements of the military with regard to reliability. So, in tests in the Air Force Research Institute in the fall of 1945, a gun of three “three-point” La-7 aircraft (each with three B-20s) that took part in the tests failed to achieve the required figure of 5,000 rounds fired from one aircraft without failures - on average, this indicator amounted to 3200 shells from an aircraft [3] . However, V. B. Shavrov claims that “initially there were complications when shooting, but in two months everything returned to normal” [12] .
| Production B-20, pcs. (according to [3] Shirokorada) | |||||||
| 1944 | 1945 | During the war | 1946 | 1947 | 1948 | 1949 | For all the time |
| 2275 | 7240 | 9515 | 440 | 780 | 1686 | 2931 | 15 352 |
According to Novikov, the main manufacturer of guns was the Kovrov Plant No. 2 named after Kirkizha , which during the war fired about 9 thousand guns. [13]
According to A. S. Yakovlev , [14] only during the war, as many as 32 thousand cannons were made [15] .
It is believed [16] that the use of the B-20 for arming the La-7 was a mistake.
Modifications
- B-20M - motor gun (for installation in the collapse of the cylinder block ).
- B-20S - version with a synchronizer (for firing through a propeller ).
- Shirokorad [3] and Shavrov [17] also claim the existence of a wing variant, but no data are available on its use.
- Perov and Rastrenin write that the B-20T-E gun was used as part of the AAU VU-9 on serial IL-10s from August 1945 [18] . In other sources, the same Rastrenin [19] mentions the use of BT-20 on VU-9 (albeit on IL-8). In the documentary film of the Civil Aviation Research Institute of the Air Force of 1945 about IL-8 (inaccessible link), it is also shown and talks about BT-20.
- In 1946 [3] , the production of the B-20E (electrified) was launched, which was used as a defensive weapon on the Tu-4 strategic bomber [20] . Then [21] it was installed instead of one of the NS-23s on Lavochkin’s “120R” plane [22] .
- In 1951, at the plant number 23 Tu-2S bombers with B-20EN guns were manufactured [23] . The following year, these guns were installed on the Il-10M attack aircraft as part of the VU-9M aircraft gun mount - a VU-9 modification with an electric drive [24] .
Application
On fighters
| Use of the B-20 on Soviet fighters | |||||||||||||
| KB | OKB Lavochkina | OKB Yakovlev | OKB Mikoyan | ||||||||||
| LA | La 7 [sn 3] | La-7p | 120P | Yak-9UV | Yak-9UT | Yak-9S | Yak-9P VK-107A | Yak-3 VK-107A | Yak-3P | Yak-3U | I-250 | ||
| Year | 1944/1945 [25] | 1945 / - | 1946 / - | 1945 / - [26] | 1945/1945 [27] | 1945 / - [28] | 1946/1947 [29] | 1944/1945? [thirty] | 1946? / 1946 | 1945/1945 [31] | 1945 / - [32] | 1945/1945 [33] | |
| A gun | 3 × B-20S | 2 × B-20 [12] | B-20E | B-20M [26] | 2 × B-20S + H-37 [d 4] [27] | 2 × B-20S + NS-23 [28] | 2 × B-20S + B-20M [sn 5] [29] | 2 × B-20S [30] | 2 × B-20S + B-20M [30] | 2 × B-20S + B-20M [31] | 2 × B-20S + B-20M [32] | 2 × B-20S + B-20M | |
| AAU | synchronous | synchronous | motor | synchronous and motor | synchronous | synchronous and motor | synchronous | synchronous and motor | |||||
| BC, sn. | 3 × 170 [sn 6] [34] | ? | 100 [22] | 100 [26] | 2 × 120 [sleep 7] [27] | 2 × 120 [sn 8] [28] | 2 × 120 + 115 [29] | 2 × 120 [30] | 3 × 100 [30] | 120 + 2 × 130 [31] | 2 × 120 [32] | 3 × 100, [33] according to other source [35] . 3 × 160 | |
How Defensive Weapons
| Use of the B-20 as a defensive weapon | ||||||||||||||||
| KB | Design Bureau Ilyushin | OKB-23 | OKB Tupolev | OKB Sukhoi | OKB Beriev | OKB Antonov | ||||||||||
| LA | IL-8 | IL-10 | IL-16 | IL-10M | IL-22 | DB-108 | Pe-2M | Tu-4 [Sun 9] | Tu-2D (65) | Tu-2D (67) | Tu-2S | Tu-8 | Tu-75 | Su-12 | Be-6 | An-2NAK |
| Year | 1944 / - [36] | 1944 / | 1945 / - | 1951/1952 | 1947 / - | 1945 / - [37] | 1945 / - [38] | 1947/1948 | 1946 / - [39] | 1946 / - [40] | ? / 1951 [mon 10] [23] | 1947 / - [41] | 1950 / - [42] | 1947 / - [43] | 1948 / - [Sun 11] | 1949 / - |
| A gun | BT-20 or B-20T-E (see above ) | B-20EN | 2 × B-20E [44] | several UB-20 [sn 12] [37] | 3 × UB-20 [sn 13] [38] | 4 × (2 × B-20E) + 3 × B-20E, [sn 14] [20] according to other source [45] 10 × B-20E | BD-20E | 2 × B-20 [40] | B-20EN, [23] according to other source BD-20E | up to 3 × UB-20 [sn 15] | 4 × B-20E [46] | 2 × B-20 | BD-20E | |||
| AAU | WU-9 | VU-9M | VDB-5 [47] | Daewoo et al. [37] . | VU-5-20 + LUS-20 | PV-20 = 4 × VDB-2 +? [48] | Wind turbine-1 [39] | n / a | Wind turbine-1 [23] | VTE-2 + KG-1 [49] | SEB-3A [50] | Wind turbine-1 | ||||
| rear turret | upper [47] | top, hatch and KU [Sun 15] | back and bottom | 4 turrets and 1 KU [20] | medium [40] | back | unsuccessful, [sn 16] back and lower | 3 turrets and 1 KU [42] | unsuccessful, [sn 17] top and KU | upper [47] | back | |||||
| BC, sn. | 150 | 800 [47] | not less than 80 [37] | 120 + 200 + 200 [38] | 5297 [Sun 18] [20] | 200 [40] | n / a | n / a | 100 + 360 + 200 [49] | 400 [47] | ||||||
There was also an unrealized project of a Su-10 jet bomber with five B-20E guns as defensive weapons and a project of a T-117 transport aircraft with LU-68 gun mounts with a UBT and SEB-3A machine gun [51] with B-20 [52] .
In addition, it never took off, although the high-altitude modification DB-108 passed through ground tests - the Myasishchev bomber VB-109 with two B-20 cannons [53] .
IL-10 attack aircraft (according to some sources, [54] in the amount of 93 pieces, and according to others, [55] about 50) were used [56] in the Korean War , but information about whether they were armed with the B-20, ShVAK or UB could not be found.
Performance Specifications
| Weapon type | single barrel automatic gun |
|---|---|
| Caliber | 20 × 99 mm R |
| Operating principle | removal of powder gases |
| Gun length | 2035 mm |
| Gun mass | 25 kg |
| Rate of fire | for synchronous version 600 rounds / min., for wing and turret - 800 rounds / min. |
| Barrel length | 1588 mm |
| Muzzle velocity | 750-800 m / s |
| Muzzle energy | 30.7 kj |
| Mass of a second volley | 0.95-1.2 kg |
| Ammunition | BZ armor-piercing incendiary mass of 97 g. Armor penetration of 14 mm armor / 400 m |
| OZ fragmentation incendiary mass of 96 g | |
| Total produced | 15 352 pcs. |
| Used on airplanes | LaGG-3 , La-5 , La-7 , Yak-1 , Yak-3 P, Yak-7b , Tu-2 , IL-2 and IL-10 |
Notes
Footnotes
- ↑ With fragmentation incendiary and armor-piercing incendiary shells
- ↑ For synchronous installations
- ↑ T. n. "Three-point".
- ↑ The modification went with the NS-23 motor gun.
- ↑ Sometimes, instead of the B-20M, it was possible to install the NS-37 or N-45, and in the latter case, one of the B-20S was removed.
- ↑ 170 rounds per gun. On the La-5 standard of 1944 - 3 × 150 [1]
- ↑ Only 20 mm ammunition.
- ↑ Excluding ammunition of caliber 23 mm in the amount of 60 pieces.
- ↑ From the eighth series to mid-1949
- ↑ This refers to the modification with the B-20EN, the date of the first flight of which is not given in the sources.
- ↑ The variant with the HP-23 went into the series.
- ↑ Varies by option.
- ↑ One of them is course, that is, formally not a defensive weapon.
- ↑ A total of 11 trunks.
- ↑ 1 2 A UB machine gun was also installed.
- ↑ Fixed installation in the bow, under the pilot's seat.
- ↑ Fixed installation in the bow, under the pilot's cabin, bottom-left in the direction of travel.
- ↑ 800 shells to the upper front, 540 to the lower front, 840 to the lower rear turret and 1700 to the stern. If you add everything, it turns out 3880.
Sources
- ↑ 1 2 Menshchikov N.G. Album of the designs of cartridges for small and large-caliber automatic weapons (from 6.5 to 37 mm). - M .: Artillery Academy. Dzerzhinsky , 1946 .-- S. 36 .-- 198 p.
- ↑ Romanov D.I. Chapter 4. Missile and artillery armament of aircraft during the Second World War (1939-1945) // 4.5. Improving and creating new aircraft installations for aircraft guns and machine guns // Air Combat Weapon . - M .: Military affairs, 2000 .-- 155 p.
- ↑ 1 2 3 4 5 6 Shirokorad A. B. 20-mm Berezin gun // History of aircraft weapons . - Minsk: Harvest, 1999 .-- 560 s. - 11,000 copies. - ISBN 985-433-695-6 .
- ↑ 1 2 3 4 5 6 Romanov D. I. Chapter 4. Missile and artillery armament of aircraft during the Second World War (1939-1945) // 4.3. Improving aircraft machine guns and cannons during the war // Weapon of air combat . - M .: Military affairs, 2000 .-- 155 p.
- ↑ Aviation and time 2009 06 // Line of fate
- ↑ GKO Decisions in 1941
- ↑ Clarification of the contents of Decree No. GKO-106ss of July 11, 1941 “On Testing a 20 mm Berezin Aircraft Gun” - “Chronology of Aviation and Aviation Industry of Russia and the USSR, 1916-1946”, Ivan Rodionov
- ↑ Novikov, 1988 , p. 197.
- ↑ 1 2 Novikov, 1988 , p. 196.
- ↑ Decisions of T-bills in 1944
- ↑ La 7 is the best of the breed
- ↑ 1 2 Shavrov, V. B. Fighters of the Lavochkin Design Bureau // History of aircraft designs in the USSR 1938-1950 . - M .: Mechanical Engineering, 1988 .-- 568 p. - 20,000 copies. - ISBN 5-217-00477-0 .
- ↑ Novikov, 1988 , p. 198.
- ↑ Yakovlev A.S. 50 years of Soviet aircraft construction. - M .: Nauka, 1968 .-- 204 p. - 15,000 copies.
- ↑ Romanov D.I. Chapter 4. Missile and artillery armament of aircraft during the Second World War (1939-1945) // 4.8. Selfless labor of the rear - to the front // Weapon of air combat . - M .: Military affairs, 2000 .-- 155 p.
- ↑ Aircraft weapons of the USSR - B-20
- ↑ Shavrov B. B. Chapter 5 Artillery (small arms) armament of Soviet aircraft 1918-1950. (brief review) // History of aircraft designs in the USSR 1938-1950 . - 3rd, corrected. - M .: Mechanical Engineering, 1994. - T. 2. - 544 p. - 7000 copies. - ISBN 5-217-00477-0 . Archived July 16, 2011. Archived July 16, 2011 on Wayback Machine
- ↑ Aviation and astronautics No. 12, 2001 // Vladimir Perov, Oleg Rastrenin. Maneuverable
- ↑ O. Rastrenin - The “Simple” History of an IL-8 Aircraft (inaccessible link)
- ↑ 1 2 3 4 Shirokorad A. B. Defensive armament of the Tu-4 bomber // History of aircraft armament . - Minsk: Harvest, 1999 .-- 560 s. - 11,000 copies. - ISBN 985-433-695-6 .
- ↑ 1. AVIATION GUNS - Military parity
- ↑ 1 2 Lavochkin La-120P
- ↑ 1 2 3 4 Tu-2 Bomber - Factories No. 23.39, 82
- ↑ Aircraft collection No. 1, 2005 // O. V. Rastrenin. Il-10 attack aircraft // Il-10M attack aircraft
- ↑ Lavochkin La-7
- ↑ 1 2 3 Yakovlev Yak-9UV
- ↑ 1 2 3 Yakovlev Yak-9UT
- ↑ 1 2 3 Yakovlev Yak-9S
- ↑ 1 2 3 Yakovlev Yak-9P VK-107
- ↑ 1 2 3 4 5 Yakovlev Yak-3 VK-107
- ↑ 1 2 3 Yakovlev Yak-3P
- ↑ 1 2 3 Yakovlev Yak-3U
- ↑ 1 2 Mikoyan, Gurevich I-250 (MiG-13)
- ↑ Technical description of the La-7
- ↑ Gunston, Bill . The Osprey Encyclopedia of Russian Aircraft 1875-1995. - 2. - London: Osprey Aerospace, 1995 .-- P. 183. - 526 p. - (General Aviation Series). - ISBN 1-85532-405-9 .
- ↑ Ilyushin IL-8
- ↑ 1 2 3 4 Myasischev DB-108
- ↑ 1 2 3 Myasischev Pe-2M
- ↑ 1 2 Tupolev Tu-2D (65)
- ↑ 1 2 3 4 Tupolev Tu-2D (67)
- ↑ Tupolev Tu-8 (inaccessible link)
- ↑ 1 2 Tupolev Tu-75
- ↑ Sukhoi Su-12
- ↑ Ilyushin IL-22
- ↑ Tupolev Tu-4
- ↑ Shavrov B. B. Chapter 3 Post-war aircraft (1945-1950) - Aircraft Design Bureau P.O. Sukhoi // History of aircraft designs in the USSR 1938-1950 . - 3rd, corrected. - M .: Mechanical Engineering, 1994. - T. 2. - 544 p. - 7000 copies. - ISBN 5-217-00477-0 . Archived July 16, 2011. Archived July 16, 2011 on Wayback Machine
- ↑ 1 2 3 4 5 4. TOWER CANNON INSTALLATIONS - Military parity
- ↑ Tu-4 heavy bomber (B-4, product “R”) - Domestic bombers 1945-2000 Archived on December 7, 2013.
- ↑ 1 2 Corrector Su-12 (inaccessible link) Aviation and Cosmonautics 2007 10
- ↑ _13. Aircraft Design Bureau named after G. M. BERIEV - Military parity
- ↑ Bartini T-117
- ↑ YOU. Aviation cannons and machine guns (USSR)
- ↑ Shavrov B. B. Chapter 2 Aircraft of the Great Patriotic War (1941-1945) - Aircraft of the Design Bureau of V. Myasishchev // History of aircraft designs in the USSR 1938-1950 . - 3rd, corrected. - M .: Mechanical Engineering, 1994. - T. 2. - 544 p. - 7000 copies. - ISBN 5-217-00477-0 . Archived July 16, 2011. Archived July 16, 2011 on Wayback Machine
- ↑ Combat use of IL-10 - heavy attack aircraft
- ↑ War in the Air No. 8, IL-2 / IL-10 History of Creation and Application // Export
- ↑ War in the air No. 8, IL-2 / IL-10 History of creation and use // IL-2 and IL-10 in battles
Literature
- Novikov V.N. Weapon of air combat // On the eve and in the days of testing . - M .: Politizdat, 1988 .-- S. 196-198. - 398 p. - (Memories). - 200,000 copies. - ISBN 5-250-00232-3 .
Links
- VIF2 NE - about the development of UB-20 in 1941 (inaccessible link)